Such a brake valve is, for example, known from DE 195 14 733 B4. The purpose of the brake valve is to brake a trailer coupled with an agricultural utility vehicle, for example a tractor, via the tractor. In this connection, the brake valve is supplied via a pump. Between the brake valve and the pump is located a control device, through which hydraulic fluid can be supplied to either the brake valve or another consumer. The exact design of such a brake valve appears from the company brochure “Hydraulisches Anhänger-Bremsventil (Hydraulic trailer brake valve)”, code number 1 987 760 506/11.99 of the company Bosch Rexroth AG, 71701 Schwieberdingen, Germany.
It is true that such a brake valve is particularly appropriate with trailers having a high weight. However, the cost of such an additional brake valve is not insignificant. Also, additional pipes, connections and sealings must be provided.